This luna moth Almost Everything Ruler is 8.5 inches long by 3" high. The design features a luna moth with forest plants amongst the night sky with stars and a crescent moon. To use the swatch part of the tool, hold it up against your stitch work and count how many stitches fit inside the cut-out area. By placing the tool over your work, you can see how many stitches you have per inch and per centimeter. The top slot measurements are in inches and side slot measurements are in centimeters. The bottom is used for stitch gauge and side is used for row gauge. This ruler is great for all fiber artists. Wraps per inch (WPI) is a way to measure the thickness of a yarn. This tool is used by spinners, but is also helpful for knitters and crocheters to determine the weight of the yarn and what the approximate gauge will be. This guide also has lines on the back to measure your yarn against, including lace, fingering, sport, DK, worsted, bulky and super bulky. To measure twist angle, lay your